1. Field of the Invention
The present invention relates to a discharge valve for use in a reciprocating compressor, and more particularly to a discharge valve for a compressor comprising a valve spring and a valve retainer for supporting a valve plate adapted to open or close a discharge port.
2. Description of the Related Art
In general, a discharge valve for a compressor, as shown in FIG. 1, is installed at an outlet of a cylinder block 5, and is adapted to control the outflow of fluid compressed in a compression chamber 6.
Such a discharge valve comprises a valve seat 1 coupled to the cylinder block 5, and a valve plate 2, a valve spring 3, and a retainer 4, which are successively assembled to the valve seat 1.
The valve seat 1 is formed with a discharge port 1a, through which the fluid compressed in the compression chamber 6 is discharged, and is further formed with a recessed portion 1b for use in the mounting of the valve plate 2, the valve spring 3, and the retainer 4.
The valve plate 2 is designed to open or close the discharge port 1a, and the valve spring 3 serves to reinforce the stiffness of the valve plate 2 in order to increase a damping force and restoring force thereof. In addition, the retainer 4 serves to limit a maximum displacement of both the valve plate 2 and the valve spring 3, thereby preventing any possible damage to the discharge valve.
Now, the opening and closing operations of the discharge valve for a compressor configured as stated above will be explained.
If a piston (not shown), adapted to reciprocate in the compression chamber 6 of the cylinder block 5, is advanced to compress the fluid in the compression chamber 6, and thereby a pressure level of the compressed fluid overcomes a support force of the valve plate 2 and the valve spring 3, the compressed fluid pushes the valve plate 2 to open the discharge port 1a, and is discharged out of the compression chamber 6 through the open discharge port 1a. 
On the contrary, if the piston (not shown) is retracted, and thereby the interior pressure of the compression chamber 6 is lowered, the valve plate 2 is restored to close the discharge port 1a by virtue of an elastic restoring force of the valve spring 3 and a suction force of the compression chamber 6.
However, the above described conventional discharge valve for use in a reciprocating compressor has a problem in that, due to the fact that the valve spring 3 and the retainer 4, which are successively mounted downstream from the valve plate 2 as shown in FIG. 2, take the form of a flat bar, they may obstruct the outflow of the compressed fluid through the discharge port 1a, thereby possibly causing flow loss.
In addition, since the valve spring 3 is generally made of spring steels, etc., it has a limitation of reducing stiffness without a reduction in size and thus has a difficulty of improving flexural elasticity thereof.